Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-9
TLE Epoch: 2023 4 4.  Predictions up to the next  14.0 days:

     Date     Time(NOAA-21) NOAA-21 Lat/Lon Date Time(LANDSAT-9) LANDSAT-9 Lat/Lon    Distance(km)  Time Diff(sec)
 04/04/2023   15:18:13   (  70.11, -53.39) 04/04/2023   15:18:57  (  70.09, -53.39)    2.73                44
 04/04/2023   16:08:54   ( -69.97, 114.14) 04/04/2023   16:08:27  ( -69.97, 114.09)    1.87                27
 04/07/2023   06:44:37   ( -71.10,-106.52) 04/07/2023   06:45:43  ( -71.01,-103.78)   99.74                66
 04/07/2023   07:35:03   (  70.05,  62.48) 04/07/2023   07:35:26  (  70.03,  62.42)    3.15                23
 04/07/2023   08:25:45   ( -69.96,-130.07) 04/07/2023   08:24:55  ( -69.98,-130.03)    2.10                50
 04/09/2023   23:01:13   ( -70.32,  10.53) 04/09/2023   23:02:24  ( -70.27,  10.99)   18.11                71
 04/09/2023   23:51:54   (  70.06, 178.25) 04/09/2023   23:51:53  (  70.05, 178.32)    2.70                 1
 04/10/2023   00:42:35   ( -69.91, -14.21) 04/10/2023   00:41:23  ( -69.94, -14.20)    2.86                72
 04/12/2023   15:17:59   ( -70.13, 126.62) 04/12/2023   15:18:52  ( -70.13, 126.68)    2.33                53
 04/12/2023   16:08:43   (  70.02, -65.91) 04/12/2023   16:08:19  (  70.02, -65.83)    2.81                24
 04/12/2023   16:59:10   ( -69.13, 102.70) 04/12/2023   16:58:02  ( -69.20, 100.69)   79.95                68
 04/15/2023   07:34:48   ( -70.05,-117.47) 04/15/2023   07:35:19  ( -70.07,-117.52)    3.29                31
 04/15/2023   08:25:32   (  69.94,  50.00) 04/15/2023   08:24:46  (  69.95,  49.96)    1.89                46
 04/17/2023   23:01:01   (  70.39,-169.54) 04/17/2023   23:02:12  (  70.29,-168.96)   24.62                71
 04/17/2023   23:51:38   ( -70.03,  -1.66) 04/17/2023   23:51:45  ( -70.02,  -1.71)    2.34                 7
 04/18/2023   00:42:22   (  69.93, 165.80) 04/18/2023   00:41:11  (  69.95, 165.85)    3.32                71